Preparation method and application of high-efficiency stable titanium dioxide supported nickel-based non-noble metal catalyst

Abstract

This invention relates to a method for preparing a highly efficient and stable titanium dioxide-supported nickel-based non-precious metal catalyst and its application. Nickel-based hydroxide powder is prepared using a non-precious metal salt as a metal precursor. The prepared nickel-based hydroxide powder is then uniformly mixed with titanium dioxide and calcined under high-temperature hydrogen conditions to form a titanium dioxide-supported nickel-based non-precious metal catalyst. Compared with traditional nickel-based non-precious metal catalysts, this titanium dioxide-supported nickel-based non-precious metal catalyst can effectively catalyze the hydrogen oxidation reaction under alkaline conditions within a potential range of 0–1.2 volts. The titanium dioxide-supported nickel-based non-precious metal catalyst prepared by this invention, when used as an electrocatalyst for hydrogen oxidation reactions under alkaline conditions, offers advantages such as simple preparation method, high reactivity, high stability, and low cost, and has broad application prospects in the field of electrochemical energy storage and conversion.

Description

Technical Field

[0001] This invention belongs to the field of functional materials and new energy technology, specifically relating to a method for preparing a highly efficient and stable titanium dioxide-supported nickel-based non-precious metal catalyst and its application. Background Technology

[0002] Hydrogen-oxygen fuel cells, as electrochemical energy conversion devices, can convert the chemical energy stored in hydrogen and oxygen into electrical energy. Currently, the most mature hydrogen-oxygen fuel cell is the proton exchange membrane fuel cell (PEMFC). Toyota launched a commercial electric vehicle powered by a PEMFC in 2015, but its anode and cathode are highly dependent on precious metal-based catalysts, making catalyst costs account for 21% of the total fuel cell cost. The high price of catalysts hinders the further large-scale commercialization of PEMFCs as on-board power systems. In contrast, replacing the acidic medium of the fuel cell with an alkaline medium, i.e., developing alkaline anion exchange membrane fuel cells, offers a new approach to reducing the total cost of fuel cells. Under alkaline operating conditions, not only is the cost of anion exchange membranes lower than that of proton exchange membranes, but the catalytic reaction conditions are also milder, allowing the use of relatively stable and inexpensive non-precious metal catalysts under alkaline conditions. However, current research shows that even platinum, the best catalyst for the anodic hydrogen oxidation reaction (HOR), has an exchange current density of only 10 under alkaline conditions. -3 Amperes per square centimeter, compared to 10 under acidic conditions -1 The ampere / cm² speed is two orders of magnitude slower. Therefore, developing efficient and stable non-precious metal catalysts for HOR under alkaline conditions is of great significance.

[0003] Research indicates that nickel is currently the only non-precious metal material with HOR (Hyperion of Reactive Hydrogen) performance. Therefore, research on nickel-based HOR electrocatalysts has received considerable attention and has developed rapidly. However, as a non-precious metal, nickel-based materials have consistently failed to overcome the fatal problem of poor stability; that is, nickel-based non-precious metal electrocatalysts are highly susceptible to self-oxidation at high potentials, thus losing their HOR catalytic performance. The deactivation potential of nickel monometallic electrocatalysts relative to the reversible hydrogen electrode (RHE) is approximately 0.1 volts. With ongoing research, the performance of nickel-based HOR non-precious metal electrocatalysts has been significantly improved. Currently, nickel-based electrocatalysts with relatively high stability and activity include NiMo (deactivation potential approximately 0.2 volts), NiW (deactivation potential approximately 0.2 volts), Ni / MoO2 (deactivation potential approximately 0.2 volts), Ni3N / C (deactivation potential approximately 0.26 volts), NiWCu (deactivation potential approximately 0.3 volts), and PS-MoNi (deactivation potential approximately 0.32 volts). However, these catalysts still cannot meet the actual operating conditions of fuel cells. This is because, during fuel cell operation, the anode voltage increases significantly due to mass transfer limitations. Furthermore, fuel shortages in fuel cells (especially during start-up and shutdown) lead to high anode potentials (approximately 0.8–0.9 volts). Currently, no non-precious metal catalyst can maintain HOR activity at such high potentials. Therefore, in addition to excellent HOR performance, the stability of non-precious metal electrocatalysts is also a pressing and extremely challenging critical issue.

[0004] Patent CN112473685A discloses a supported amorphous hydrazine hydrate catalytic hydrogen production catalyst and its preparation method. It uses hydrophilic anatase-type crystal structured nano-TiO2 as a support and employs an impregnation co-reduction method to reduce non-noble metal Ni and Mo precursors in a controlled ratio using sodium borohydride to prepare a supported amorphous nanocatalyst with a high specific surface area. The TiO2 support retains its anatase-type crystal structure, while the main active component of the catalyst, NiMo, exhibits a highly active amorphous structure. However, this patented preparation method uses an impregnation co-reduction method to load amorphous NiMo onto anatase-type TiO2, without calcining to form a strong interaction between the NiMo metal and the TiO2 support. Patent CN107275653A utilizes the hydrolysis reaction of titanium dioxide precursors to form a titanium dioxide nanocoating layer on a functionalized carbon support. Simultaneously, transition metal ions such as Pd, Os, Ru, Ir, Rh, Ni, Co, and Mo are chelated through titanium dioxide dangling bonds. Finally, heat treatment under a reducing atmosphere forms a carbon-supported non-platinum hydrogenation catalyst for fuel cells with transition metals embedded in the titanium dioxide interface. This catalyst exhibits significantly superior hydrogenation catalytic activity and stability compared to commercial Pt / C and PtRu / C under acidic and alkaline conditions. However, the above preparation method involves the functionalization of the carbon support, increasing the complexity of the preparation process. While the catalyst prepared by this method shows improved stability during catalytic hydrogenation, its stability still cannot meet the requirements of high anode potentials in practical applications. Summary of the Invention

[0005] This invention addresses the technical shortcomings of poor stability in current alkaline fuel cell anode nickel-based non-precious metal HOR electrocatalysts by providing a method for preparing a highly efficient and stable titanium dioxide-supported nickel-based non-precious metal catalyst and enabling it to effectively catalyze hydrogen oxidation under alkaline conditions at high potential.

[0006] The technical solution of this invention is as follows: a method for preparing a highly efficient and stable titanium dioxide-supported nickel-based non-precious metal catalyst, comprising the following steps: preparing nickel-based hydroxide precursor powder using a non-precious metal salt as a metal precursor, then uniformly mixing it with titanium dioxide and calcining and pyrolyzing it under high-temperature hydrogen conditions to form a titanium dioxide-supported nickel-based non-precious metal catalyst.

[0007] (1) Dissolve nickel salt and molybdate in ultrapure water in a predetermined ratio, then add ethylene glycol and ammonia. After the above liquids are mixed evenly, carry out a high-temperature reaction to prepare nickel-based hydroxide precursor.

[0008] (2) The nickel-based hydroxide precursor obtained in step (1) is thoroughly mixed with a predetermined amount of titanium dioxide;

[0009] (3) The light green powder obtained in step (2) is subjected to high-temperature calcination under a hydrogen atmosphere to obtain the novel, efficient and stable titanium dioxide supported nickel-based non-precious metal catalyst.

[0010] This invention uses titanium dioxide as a carrier and achieves efficient electron transfer from titanium to nickel through strong metal carrier interactions between titanium dioxide and nickel-based single metals, binary alloys (NiMo, NiW, NiCo, NiFe, NiCu, NiMn, etc.) and multi-element alloys (NiWCu, NiCoMo, etc.), thereby enhancing the stability of HOR catalyzed by nickel-based non-noble metal electrocatalysts under alkaline conditions.

[0011] This invention utilizes a composite catalyst formed by calcination and reduction in a hydrogen atmosphere to generate crystalline NiMo supported on a TiO2 support. The resulting strong interaction promotes electron transfer between Ni and Ti, significantly improving the stability of the NiMo / TiO2 catalytic hydrogen oxidation reaction.

[0012] Preferably, in the preparation method of the titanium dioxide supported nickel-based non-precious metal catalyst, the nickel salt is nickel sulfate, nickel nitrate, or nickel chloride, etc.

[0013] Preferably, in the preparation method of the titanium dioxide supported nickel-based non-noble metal catalyst, the molybdate is sodium molybdate or ammonium molybdate, etc.

[0014] Preferably, in the preparation method of the titanium dioxide supported nickel-based non-precious metal catalyst, molybdate can be replaced with tungstate, copper salt, iron salt, cobalt salt, and manganese salt, etc.

[0015] Preferably, in the preparation method of the titanium dioxide supported nickel-based non-precious metal catalyst, the molar ratio of nickel to other non-precious metals is 1 to 10:1.

[0016] Preferably, in the preparation method of the titanium dioxide supported nickel-based non-precious metal catalyst, the ratio of water: ethylene glycol: ammonia is 1-5:10-20:1 (volume ratio).

[0017] Preferably, in the preparation method of the titanium dioxide supported nickel-based non-precious metal catalyst, the high-temperature reaction is carried out by hydrothermal, solvothermal, oil bath, water bath and microwave-assisted heating, etc., with a temperature of 130 to 200 degrees Celsius and a duration of 5 to 120 minutes.

[0018] Preferably, in the preparation method of the titanium dioxide supported nickel-based non-precious metal catalyst, the titanium dioxide includes commercial titanium dioxide and titanium dioxide prepared by various methods, and the crystal structure includes anatase, rutile and brookite.

[0019] Preferably, in the preparation method of the titanium dioxide supported nickel-based non-precious metal catalyst, the molar ratio of nickel to titanium dioxide is 1:1 to 0.1.

[0020] Preferably, in the preparation method of the titanium dioxide supported nickel-based non-precious metal catalyst, the mixing conditions are that the two are dispersed in a dispersant such as ethanol or water, and the resulting material is thoroughly ground for 10 to 60 minutes.

[0021] Preferably, in the preparation method of the titanium dioxide supported nickel-based non-precious metal catalyst, the calcination conditions are H2 / N2 or H2 / Ar atmosphere, the heating rate is 1-10 degrees Celsius / minute, the calcination temperature is 300-700 degrees Celsius, and the calcination time is 30-180 minutes.

[0022] The application of a novel, highly efficient, and stable titanium dioxide-supported nickel-based non-precious metal catalyst, as described above, is as an electrocatalyst used in electrochemical energy storage and conversion reactions. These electrochemical energy storage and conversion reactions include fuel cell electrode reactions (hydrogen oxidation, methanol oxidation, ammonia oxidation, and oxygen reduction reactions, etc.) and water electrolysis electrode reactions (oxygen evolution reaction and hydrogen evolution reaction, etc.).

[0023] The catalyst obtained by the method of this invention uses titanium dioxide as a support, and achieves efficient electron transfer from titanium to nickel through strong metal-support interactions between titanium dioxide and nickel-based single metals, binary alloys (NiMo, NiW, NiCo, NiFe, NiCu, NiMn, etc.), and multi-component alloys (NiWCu, NiCoMo, etc.). The electronic effect of this catalyst optimizes and regulates both the stability and activity of nickel-based non-precious metal catalysts, achieving efficient catalysis of HOR at high anodic potentials. The stability of this highly efficient and stable titanium dioxide-supported nickel-based non-precious metal catalyst is relative to that of unsupported nickel-based metals. For titanium dioxide-supported nickel-based non-precious metal catalysts, the introduction of the titanium dioxide support effectively avoids the deactivation of active sites during high-potential catalysis.

[0024] The titanium dioxide-supported nickel-based non-precious metal catalyst of this invention can maintain good catalytic performance for hydrogen oxidation reaction even at an anode potential of up to 1.2 volts under alkaline conditions, which is a significant improvement compared with conventional nickel monometallic catalysts (deactivated at about 0.1 volts) and nickel-based alloy catalysts (deactivated at about 0.2 volts).

[0025] Compared with the prior art, the main advantages of the present invention are reflected in the following aspects:

[0026] (1) The preparation method of the novel, efficient and stable titanium dioxide supported nickel-based non-precious metal catalyst of the present invention is simple, has universality for nickel-based non-precious metals, has low preparation cost, and is suitable for large-scale commercial production.

[0027] (2) The novel, highly efficient, and stable titanium dioxide-supported nickel-based non-precious metal catalyst of this invention can achieve excellent catalytic activity and stability of nickel-based non-precious metal electrocatalysts for alkaline HOR at high potentials. It has potential value in practical applications such as anion exchange membrane fuel cells. Attached Figure Description

[0028] Figure 1 This is a transmission electron microscope (TEM) image of the titanium dioxide-supported nickel-based non-noble metal catalyst (NiMo / TiO2) prepared in Example 1.

[0029] Figure 2 The image shows the X-ray diffraction (XRD) pattern of the titanium dioxide-supported nickel-based non-noble metal catalyst (NiMo / TiO2) prepared in Example 1.

[0030] Figure 3 The graph shows the catalytic performance of the titanium dioxide-supported nickel-based non-precious metal catalyst (NiMo / TiO2) prepared in Example 1 and the NiMo catalyst prepared by the same method in the hydrogen oxidation reaction. The test electrolyte was 0.1 mol / L NaOH saturated with hydrogen; the rotating disk electrode speed was 1600 rpm; the electrode prepared by the nickel-based non-precious metal electrocatalyst was the working electrode; the saturated calomel electrode was the reference electrode; and the graphite rod was the counter electrode.

[0031] Figure 4 The figure shows the chronoampere (it) curves of the hydrogen oxidation reaction catalyzed by the titanium dioxide-supported nickel-based non-precious metal catalyst (NiMo / TiO2) prepared in Example 1 and the NiMo catalyst prepared by the same method. The test electrolyte was 0.1 mol / L NaOH saturated with hydrogen; the rotating disk electrode speed was 1600 rpm; the electrode prepared by the titanium dioxide-supported nickel-based non-precious metal electrocatalyst was the working electrode; the saturated calomel electrode was the reference electrode; and the graphite rod was the counter electrode.

[0032] Figure 5 The figure shows the chronoampere (it) curves of the hydrogen oxidation reaction catalyzed by the titanium dioxide-supported nickel-based non-precious metal catalyst (NiW / TiO2) prepared in Example 6 and the NiW catalyst prepared by the same method. The test electrolyte was 0.1 mol / L NaOH saturated with hydrogen; the rotating disk electrode speed was 1600 rpm; the electrode prepared by the nickel-based non-precious metal electrocatalyst was the working electrode; the saturated calomel electrode was the reference electrode; and the graphite rod was the counter electrode. Detailed Implementation

[0033] The embodiments of the present invention are described in detail below. These embodiments are implemented based on the technical solution of the present invention, providing detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.

[0034] Example 1

[0035] A method for preparing a highly efficient and stable titanium dioxide-supported nickel-based non-noble metal catalyst, comprising the following steps:

[0036] (1) Mix 735 mg Ni(NO3)2.6H2O and 81 mg (NH4)6Mo7O 24 Dissolve .4H2O in 2.5 mL of H2O, then add 12.5 mL of ethylene glycol and 1 mL of NH3·H2O, and stir thoroughly for 2 hours.

[0037] (2) Transfer the above solution to a Teflon-lined stainless steel autoclave and react at 190 degrees Celsius for 1 hour. After cooling to room temperature, wash five times with ethanol and water by centrifugation.

[0038] (3) The green precipitate obtained in (2) was mixed with 50 mg TiO2 in 50 mL of ethanol dispersant, and the mixture was magnetically stirred for 20 hours before being separated by vacuum filtration. The resulting green substance was dried in a vacuum at 50°C. The dried powder was then thoroughly ground for 20 minutes.

[0039] (4) The powder obtained in (3) is heated to 400 degrees Celsius at a heating rate of 3 degrees Celsius / minute under a reducing atmosphere (H2 / N2), and calcined at 400 degrees Celsius for 1 hour to obtain a titanium dioxide supported nickel-based non-precious metal catalyst (NiMo / TiO2).

[0040] (5) The HOR electrochemical performance of the titanium dioxide-supported nickel-based non-noble metal electrocatalyst (NiMo / TiO2) was tested. The test electrolyte was 0.1 mol / L NaOH saturated with hydrogen at 25.0 ± 0.5 degrees Celsius; the working electrode was a glassy carbon rotating disk electrode with a diameter of 5.00 mm on which the prepared NiMo / TiO2 catalyst film was drop-coated; the saturated calomel electrode (SCE) and carbon rod were used as the reference electrode and the counter electrode, respectively.

[0041] The NiMo / TiO2 catalyst was tested using transmission electron microscopy (TEM), such as... Figure 1 As shown, the catalyst has a supported catalyst structure, that is, NiMo alloy particles with a particle size of about 10 nanometers are uniformly supported on a TiO2 support.

[0042] The NiMo / TiO2 catalyst was subjected to X-ray diffraction (XRD) tests, such as... Figure 2 As shown. The NiMo alloy in this catalyst is Ni4Mo; the TiO2 support crystal types are anatase and rutile, with anatase being the main component.

[0043] The catalytic performance of the NiMo / TiO2 catalyst prepared in this embodiment and the NiMo catalyst without TiO2 support prepared by the same method for hydrogen oxidation under alkaline conditions was compared. Figure 3 and Figure 4 As shown in the figure, NiMo / TiO2 can still effectively catalyze the hydrogen oxidation reaction in alkaline media at an anodic potential as high as 1.2 V, and maintain good stability.

[0044] Example 2

[0045] A method for preparing a highly efficient and stable titanium dioxide-supported nickel-based non-noble metal catalyst, comprising the following steps:

[0046] (1) Mix 735 mg Ni(NO3)2.6H2O and 81 mg (NH4)6Mo7O 24 Dissolve .4H2O in 2.5 mL of H2O, then add 12.5 mL of ethylene glycol and 1 mL of NH3·H2O, and stir thoroughly for 2 hours.

[0047] (2) Transfer the above solution to a Teflon-lined stainless steel autoclave and react at 190 degrees Celsius for 1 hour. After cooling to room temperature, wash five times with ethanol and water by centrifugation.

[0048] (3) The green precipitate obtained in (2) was mixed with 100 mg TiO2 in 50 mL of ethanol dispersant, and the mixture was magnetically stirred for 20 hours before being separated by vacuum filtration. The resulting green substance was dried in a vacuum at 50°C. The dried powder was then thoroughly ground for 20 minutes.

[0049] (4) The powder obtained in (3) is heated to 400 degrees Celsius at a heating rate of 3 degrees Celsius / minute under a reducing atmosphere (H2 / N2), and calcined at 400 degrees Celsius for 1 hour to obtain a titanium dioxide supported nickel-based non-precious metal catalyst (NiMo / TiO2).

[0050] (5) The HOR electrochemical performance of the titanium dioxide-supported nickel-based non-noble metal electrocatalyst (NiMo / TiO2) was tested. The test electrolyte was 0.1 mol / L NaOH saturated with hydrogen at 25.0 ± 0.5 degrees Celsius; the working electrode was a glassy carbon rotating disk electrode with a diameter of 5.00 mm on which the prepared NiMo / TiO2 catalyst film was drop-coated; the saturated calomel electrode (SCE) and carbon rod were used as the reference electrode and the counter electrode, respectively.

[0051] Testing showed that the titanium dioxide-supported nickel-based non-precious metal electrocatalyst (NiMo / TiO2) prepared in this embodiment exhibits good catalytic activity and stability for hydrogen oxidation under alkaline conditions.

[0052] Example 3

[0053] A method for preparing a highly efficient and stable titanium dioxide-supported nickel-based non-noble metal catalyst, comprising the following steps:

[0054] (1) Mix 735 mg Ni(NO3)2.6H2O and 81 mg (NH4)6Mo7O 24 Dissolve .4H2O in 2.5 mL of H2O, then add 12.5 mL of ethylene glycol and 1 mL of NH3·H2O, and stir thoroughly for 2 hours.

[0055] (2) Transfer the above solution to a Teflon-lined stainless steel autoclave and react at 190 degrees Celsius for 1 hour. After cooling to room temperature, wash five times with ethanol and water by centrifugation.

[0056] (3) The green precipitate obtained in (2) was mixed with 33 mg TiO2 in 50 mL of ethanol dispersant and magnetically stirred for 20 hours before being separated by filtration. The resulting green substance was dried in a vacuum at 50°C. The dried powder was then thoroughly ground for 20 minutes.

[0057] (4) The powder obtained in (3) is heated to 400 degrees Celsius at a heating rate of 3 degrees Celsius / minute under a reducing atmosphere (H2 / N2), and calcined at 400 degrees Celsius for 1 hour to obtain a titanium dioxide supported nickel-based non-precious metal catalyst (NiMo / TiO2).

[0058] (5) The HOR electrochemical performance of the titanium dioxide-supported nickel-based non-noble metal electrocatalyst (NiMo / TiO2) was tested. The test electrolyte was 0.1 mol / L NaOH saturated with hydrogen at 25.0 ± 0.5 degrees Celsius; the working electrode was a glassy carbon rotating disk electrode with a diameter of 5.00 mm on which the prepared NiMo / TiO2 catalyst film was drop-coated; the saturated calomel electrode (SCE) and carbon rod were used as the reference electrode and the counter electrode, respectively.

[0059] Testing showed that the titanium dioxide-supported nickel-based non-precious metal electrocatalyst (NiMo / TiO2) prepared in this embodiment exhibits good catalytic activity and stability for hydrogen oxidation under alkaline conditions.

[0060] Example 4

[0061] A method for preparing a highly efficient and stable titanium dioxide-supported nickel-based non-noble metal catalyst, comprising the following steps:

[0062] (1) Mix 735 mg Ni(NO3)2.6H2O and 81 mg (NH4)6Mo7O 24 Dissolve .4H2O in 2.5 mL of H2O, then add 12.5 mL of ethylene glycol and 1 mL of NH3·H2O, and stir thoroughly for 2 hours.

[0063] (2) Transfer the above solution to a Teflon-lined stainless steel autoclave and react at 190 degrees Celsius for 1 hour. After cooling to room temperature, wash five times with ethanol and water by centrifugation.

[0064] (3) The green precipitate obtained in (2) was mixed with 25 mg TiO2 in 50 mL of ethanol dispersant and magnetically stirred for 20 hours before being separated by filtration. The resulting green substance was dried in a vacuum at 50°C. The dried powder was then thoroughly ground for 20 minutes.

[0065] (4) The powder obtained in (3) is heated to 400 degrees Celsius at a heating rate of 3 degrees Celsius / minute under a reducing atmosphere (H2 / N2), and calcined at 400 degrees Celsius for 1 hour to obtain a titanium dioxide supported nickel-based non-precious metal catalyst (NiMo / TiO2).

[0066] (5) The HOR electrochemical performance of the titanium dioxide-supported nickel-based non-noble metal electrocatalyst (NiMo / TiO2) was tested. The test electrolyte was 0.1 mol / L NaOH saturated with hydrogen at 25.0 ± 0.5 degrees Celsius; the working electrode was a glassy carbon rotating disk electrode with a diameter of 5.00 mm on which the prepared NiMo / TiO2 catalyst film was drop-coated; the saturated calomel electrode (SCE) and carbon rod were used as the reference electrode and the counter electrode, respectively.

[0067] Testing showed that the titanium dioxide-supported nickel-based non-precious metal electrocatalyst (NiMo / TiO2) prepared in this embodiment exhibits good catalytic activity and stability for hydrogen oxidation under alkaline conditions.

[0068] Example 5

[0069] A method for preparing a highly efficient and stable titanium dioxide-supported nickel-based non-noble metal catalyst, comprising the following steps:

[0070] (1) Mix 735 mg Ni(NO3)2.6H2O and 81 mg (NH4)6Mo7O 24 Dissolve .4H2O in 2.5 mL of H2O, then add 12.5 mL of ethylene glycol and 1 mL of NH3·H2O, and stir thoroughly for 2 hours.

[0071] (2) Transfer the above solution to a Teflon-lined stainless steel autoclave and react at 190 degrees Celsius for 1 hour. After cooling to room temperature, wash five times with ethanol and water by centrifugation.

[0072] (3) The green precipitate obtained in (2) was mixed with 50 mg TiO2 in 50 mL of ethanol dispersant and magnetically stirred for 20 hours before being separated by filtration. The resulting green substance was dried in a vacuum at 50°C. The dried powder was then thoroughly ground for 40 minutes.

[0073] (4) The powder obtained in (3) is heated to 400 degrees Celsius at a heating rate of 3 degrees Celsius / minute under a reducing atmosphere (H2 / N2), and calcined at 400 degrees Celsius for 1 hour to obtain a titanium dioxide supported nickel-based non-precious metal catalyst (NiMo / TiO2).

[0074] (5) The HOR electrochemical performance of the titanium dioxide-supported nickel-based non-noble metal electrocatalyst (NiMo / TiO2) was tested. The test electrolyte was 0.1 mol / L NaOH saturated with hydrogen at 25.0 ± 0.5 degrees Celsius; the working electrode was a glassy carbon rotating disk electrode with a diameter of 5.00 mm on which the prepared NiMo / TiO2 catalyst film was drop-coated; the saturated calomel electrode (SCE) and carbon rod were used as the reference electrode and the counter electrode, respectively.

[0075] Testing showed that the titanium dioxide-supported nickel-based non-precious metal electrocatalyst (NiMo / TiO2) prepared in this embodiment exhibits excellent catalytic activity and stability for hydrogen oxidation under alkaline conditions.

[0076] Example 6

[0077] A method for preparing a highly efficient and stable titanium dioxide-supported nickel-based non-noble metal catalyst, comprising the following steps:

[0078] (1) Dissolve 735 mg Ni(NO3)2.6H2O and 177.5 mg (NH4)2WO4 in 2.5 mL H2O, then add 12.5 mL ethylene glycol and 1 mL NH3.H2O, and stir thoroughly for 2 hours.

[0079] (2) Transfer the above solution to a Teflon-lined stainless steel autoclave and react at 190 degrees Celsius for 1 hour. After cooling to room temperature, wash five times with ethanol and water by centrifugation.

[0080] (3) The green precipitate obtained in (2) was mixed with 50 mg TiO2 in 50 mL of ethanol dispersant, and the mixture was magnetically stirred for 20 hours before being separated by vacuum filtration. The resulting green substance was dried in a vacuum at 50°C. The dried powder was then thoroughly ground for 20 minutes.

[0081] (4) The powder obtained in (3) is heated to 500 degrees Celsius at a heating rate of 3 degrees Celsius / minute under a reducing atmosphere (H2 / N2), and calcined at 500 degrees Celsius for 1 hour to obtain a titanium dioxide supported nickel-based non-precious metal catalyst (NiW / TiO2).

[0082] (5) The HOR electrochemical performance of the titanium dioxide-supported nickel-based non-noble metal electrocatalyst (NiW / TiO2) was tested. The test electrolyte was 0.1 mol / L NaOH saturated with hydrogen at 25.0 ± 0.5 degrees Celsius; the working electrode was a glassy carbon rotating disk electrode with a diameter of 5.00 mm on which the prepared NiW / TiO2 catalyst film was drop-coated; the saturated calomel electrode (SCE) and carbon rod were used as the reference electrode and the counter electrode, respectively.

[0083] The catalytic performance of the NiW / TiO2 catalyst prepared in this embodiment and the NiW catalyst prepared by the same method for hydrogen oxidation under alkaline conditions was compared. Figure 5 As shown in the figure, NiW / TiO2 can still effectively catalyze the hydrogen oxidation reaction at an anodic potential as high as 1.2 V.

[0084] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. A method for preparing a highly efficient and stable titanium dioxide supported nickel-based non-noble metal catalyst, characterized in that, Nickel-based hydroxide precursor powder was prepared using non-precious metal salts as metal precursors, and then uniformly mixed with titanium dioxide and calcined and pyrolyzed under high-temperature hydrogen conditions to form a titanium dioxide-supported nickel-based non-precious metal catalyst. Specifically, the following steps are included: (1) Dissolve nickel salt and molybdate in ultrapure water in a predetermined ratio, then add ethylene glycol and ammonia. After the liquid is mixed evenly, carry out a high-temperature reaction to prepare nickel-based hydroxide precursor. (2) The nickel-based hydroxide precursor obtained in step (1) is thoroughly mixed with a predetermined amount of titanium dioxide; (3) The mixed powder obtained in step (2) is subjected to high-temperature calcination under a hydrogen atmosphere to obtain a highly efficient and stable titanium dioxide supported nickel-based non-precious metal catalyst.

2. The method for preparing a titanium dioxide supported nickel-based non-noble metal catalyst according to claim 1, characterized by: The nickel salt mentioned in step (1) includes one or more of nickel sulfate, nickel nitrate or nickel chloride; the molybdate includes one or two of sodium molybdate or ammonium molybdate.

3. The method of claim 1, wherein the method is characterized by: The molybdate mentioned in step (1) can be replaced by one of the following: tungstate, copper salt, iron salt, cobalt salt, or manganese salt.

4. The method for preparing the titanium dioxide-supported nickel-based non-noble metal catalyst according to claim 1, characterized in that: In step (1), the atomic molar ratio of nickel to molybdenum is 1 to 10:

1.

5. The method for preparing the titanium dioxide-supported nickel-based non-noble metal catalyst according to claim 1, characterized in that: In step (1), the volume ratio of water, ethylene glycol and ammonia is 1-5:10-20:

1.

6. The method for preparing the titanium dioxide-supported nickel-based non-noble metal catalyst according to claim 1, characterized in that: In step (1), the reaction temperature is 130 to 200 degrees Celsius and the reaction duration is 5 to 120 minutes, including heating methods such as hydrothermal, solvothermal, oil bath, water bath, and microwave heating.

7. The method for preparing the titanium dioxide-supported nickel-based non-noble metal catalyst according to claim 1, characterized in that: The titanium dioxide crystal structure described in step (2) includes one of anatase, rutile, or brookite.

8. The method for preparing the titanium dioxide-supported nickel-based non-noble metal catalyst according to claim 1, characterized in that: In step (2), the molar ratio of nickel to titanium dioxide is 1:1 to 0.

1. In step (2), the conditions for thorough mixing are that the two are uniformly dispersed in ethanol or water dispersant, and the resulting material is thoroughly ground for 10 to 60 minutes.

9. The method for preparing the titanium dioxide-supported nickel-based non-noble metal catalyst according to claim 1, characterized in that: In step (3), the calcination conditions are H2 / N2 or H2 / Ar atmosphere, the heating rate is 1 to 10 degrees Celsius / minute, the calcination temperature is 300 to 700 degrees Celsius, and the calcination time is 30 to 180 minutes.

10. The application of the titanium dioxide-supported nickel-based non-noble metal catalyst obtained by the preparation method according to claim 1, characterized in that: The titanium dioxide-supported nickel-based non-precious metal catalyst is used as an electrocatalyst in fuel cell electrode reactions or water electrolysis electrode reactions.

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